Large diameter threaded conductor casings and piles are commonly used in drilling wells in the oil and gas industry, particularly for offshore wells. Typical conductor casing sizes used in the oil and gas industry range from 16 inches to 48 inches in diameter. Large diameter threaded tubulars are also used as pilings to secure offshore structures to the seafloor. These pilings may range from 16 inches to 48 inches and larger in diameter. These tubulars typically come in joints that are 30 to 40 feet in length with a threaded pin member on one end and a threaded box member on the other end.
Make-up of such large diameter threaded conductor casings typically requires rotating an upper joint so that its threaded pin member can screw into and make-up with the threaded box member of a stationary joint located in the rotary table. Currently, most conductor make-up service companies use rope to rotate or spin the upper joint of casing to partially make-up the connection. Two manual rig tongs are then connected to the two joints of conductor pipe, one above and one below the threaded connection, to torque the connection to the final make-up value. Other conductor make-up service companies may use a power tong to rotate or spin the upper joint of casing to make-up the connection. A separate manual tong is used on the bottom joint of casing to provide backup support to prevent the lower joint from rotating relative to the first joint of casing.
The current method of making up large diameter threaded connections is a hazardous process at best, involving several pieces of large, cumbersome equipment and several personnel working on the rig floor. There are safety hazards with the use of a rope for spinning pipe and in the handling and manipulation of both manual and powered tongs.
Thus, there is a need for a system and method of making up, or breaking out, large diameter threaded conductor casing which reduce the potential for injury to the operator and equipment and to create a more cost effective, efficient operation. The present invention is directed to a system and method which addresses this need for running large diameter threaded casings and/or piles. The invention also has application in the make-up or break-out of large diameter threaded tubulars in the horizontal mode, such as the laying of new pipeline.